Field of the Invention
The present invention relates to a workpiece evaluating method of evaluating the gettering property of a workpiece.
Description of the Related Art
In recent years, a wafer having a plurality of devices formed thereon (which will be hereinafter referred to as device wafer) has been thinned for the purposes of a size reduction of each device, for example. However, when the device wafer is polished to reduce the wafer thickness to 100 μm or less, there is a possibility of reduction in gettering property of suppressing the movement of metal elements harmful to the devices, causing a faulty operation of each device. To cope with this problem, a gettering layer for capturing the metal elements is formed inside the device wafer (see Japanese Patent Laid-open No. 2009-94326, for example). In this processing method, the device wafer is ground under predetermined conditions to thereby form the gettering layer including a predetermined strained layer as maintaining the die strength of the device wafer.